10 richest people in America

•September 20, 2012

The net worth of the richest Americans grew by 13 percent in the past year to $1.7 trillion, according to Forbes magazine. The average net worth of the 400 wealthiest Americans rose to a record $4.2 billion, up more than 10 percent from a year ago. Seven in ten of the list's members made their fortunes from scratch.